Chlorine

Chlorine is a halogen, found in the periodic table in group 17.

In its elemental form (Cl2 or "Dichlorine") under standard conditions, chlorine is a powerful oxidant and is used in bleaching and disinfectants. Most chloride salts are soluble in water, thus, chloride-containing minerals are usually only found in abundance in dry climates or deep underground.

As a common disinfectant, chlorine compounds are used in swimming pools to keep them clean and sanitary. In the upper atmosphere, chlorine-containing molecules such as chlorofluorocarbons have been implicated in the destruction of the ozone layer.

When it comes to Chlorine detection, Airmet can offer you the best solution for your application. We have a wide range of portable and fixed instruments suitable for most applications.

Chlorine Characteristics

Synonyms

CAS No.

7782-50-5

Chemical formula

Cl2

Vapour density

2.5 (air = 1)

Safe Work Australia ES

TWA

1 ppm (peak limitation)

STEL

--

Flammable limits

LEL

--

UEL

--

Chemical/physical properties

Chlorine is a greenish-yellow gas at atmospheric pressure and although it is non-combustible by itself, because of its strongly oxidising nature, it is able to support the combustion of compounds containing hydrogen, e.g. hydrocarbons.

It has what is described as a suffocating odour usually detectable above 0.2 to 0.4 ppm.

Hazardous properties

Chlorine gas is a severe irritant to the mucous membranes, conjunctiva (eyes) and respiratory system and at high concentrations will act as an asphyxiant, causing cramps in the muscles of the larynx and swelling of the mucous membranes.

Occurrence/Uses

Chlorine readily reacts with most other elements to form compounds such as sodium chloride (common salt), sodium hypochlorite (domestic bleach)(1), chlorinated hydrocarbons (chloroform, trichloroethylene etc.) and some of these substances, e.g. pesticides such as DDT, dieldrin and chlordane, present their own hazards.

Chlorine gas itself does not occur naturally but is produced industrially and transported, compressed in cylinders, to be used as a raw material in chemical plants manufacturing the above and many other substances. It is also used by direct injection:

(1) as a disinfectant in water treatment plants and public swimming pools;

(2) as a bleach in the pulp and paper industry.

Detectors available

Electrochemical (0 – 50 ppm/0 – 100 ppm)

Gas detector tube (0.05 – 40 ppm)

Suggested alarm levels

Lo: 0.5 ppm

Hi: 1 ppm

Notes

(1) Mixing sodium hypochlorite (domestic bleach) with an acid such as acetic acid (vinegar) can produce chlorine gas. Do NOT try this at home!